In the first major terror strike in Tripura this year, at least two Border Security Force (BSF) troopers were killed on Friday in a bomb blast triggered by insurgents near the border with Bangladesh, police said.“A powerful improvised explosive device (IED) was exploded when BSF jawans were patrolling on foot along the India-Bangladesh border killing two para-military personnel on the spot,” police spokesman Nepal Das told reporters.The tribal guerrillas belonging to the National Liberation Front of Tripura (NLFT) also fired on the BSF personnel immediately after the blast at Ratia in northern Tripura, 170 km north of Tripura capital Agartala.Das said: “The two riflemen - Arup Das (31) and Brajendri Lal (34) - died instantly while the other BSF troopers retaliated with gunfire.”Senior police and BSF officials rushed with reinforcements to the spot and launched a combing operation to nab the extremists. The banned NLFT along with another outlawed outfit, All Tripura Tiger Force (ATTF), has been fighting for an independent tribal homeland in Tripura and operates out of Bangladesh.This was the first militant attack this year in Tripura, bordering Bangladesh. The last terror strike had taken place Nov 9 last year in which eight tribal villagers, including four women, were killed and another woman injured by NLFT rebels.The NLFT and the ATTF along with other terrorist outfits of the northeast for the past many years have been boycotting national days, Republic Day and Independence day, and observe bandhs and hoist black flags in their respective areas of domination.